1. Field of the Invention
This invention relates to an aromatic carbonate process comprising contacting a phenol, carbon monoxide, a base, a Group VIIIB element selected from ruthenium, rhodium, palladium, osmium, iridium or platinum having an oxidation state of plus one.
2. Description of the Prior Art
A. J. Chalk recognized -- as broadly disclosed in the Chalk patent applications referenced herein -- that aromatic carbonates can be prepared by contacting a phenol, carbon monoxide, a base, and a Group VIIIB element selected from ruthenium, rhodium, palladium osmium, iridium or platinum having an oxidation state greater than zero.
Unexpectedly, I have found that when a Group VIIIB element is employed at the first oxidation level greater than zero at the beginning of my aromatic carbonate process that the yields of aromatic carbonate are optimized and that by-product undesirable side reactions such as the formation of aromatic salicylates are essentially or substantially avoided.